Presently, SIP is becoming an increasingly popular protocol for transporting both standard and non-standard information in a common framework over Internet Protocol (IP) based Local Area Networks (LANs). For example, LANs including IP-based multi-media service provider systems may include systems and services provided by AT&T. However, Wide Area Networks (WANs) provided by other various communications service providers continue to employ a combination of IP-based communication devices and/or equipment and Public Switched Telephone Networks (PSTNs) or circuit-based communication devices and/or equipment, as well as a number of other circuit-based components and/or equipment. The PSTN-based communication devices use Integrated Services Digital Network User Part (ISUP) as a protocol for transporting information over the PSTN. However, each multi-media communication service provider system operating on a LAN (e.g. IP-based) is required to interface with the WAN (IP-based and/or PSTN based) in order to communicate information over the WAN to SIP-based and/or PSTN-based communication devices.
One problem arises when a request for multi-media services arrives at a multi-media services provider system operating on a LAN from an IP-based calling communication device that requires a media path to be formed between the IP-based calling communication device and a PSTN-based destination communication device. The problem relates to the fact that the SIP protocol employed by the IP-based multi-media service provider system operating on the LAN does not include a provision for including complete address specific information in outgoing SIP messages, which are sent from the multi-media services provider system to the PSTN-based communication device. As a result, the IP-based multi-media services provider system operating on the LAN is presently unable to deliver complete address specific information during setting up calls and/or forming multi-media paths between a calling communication device and destination communication device when the calling communication device is an IP-based communication device and the destination communication device is a PSTN or circuit-based communication device.
Therefore, an unsolved need remains for a SIP protocol message, such as a SIP INVITE message, which employs a format and/or parameters that permit inclusion of complete address specific information of PSTN-based or circuit-based communication devices and the originating party's Privacy Screening Indicator Information, as well as provisions for efficient processing of the addressing information.